With smoke from wildfires several kilometres away, Sarah Naugle walks her horse Lady on the grounds of Greely Road School in the Gregoire subdivision near the southern boundary of Fort McMurray, Alta., on Monday, May 2, 2016. Aircraft dropping fire retardant are working with crews on the ground to protect homes from an uncontrolled wildfire close to Fort McMurray in northern Alberta.

Image Credit: THE CANADIAN PRESS/Greg Halinda

FORT MCMURRAY, Alta. - About 500 residents have been allowed to return home in northern Alberta after a wildfire forced them out on the weekend.

Melissa Blake, mayor of the Regional Municipality of Wood Buffalo, said Monday evening the mandatory evacuation order was lifted for residents in the Prairie Creek neighbourhoods just south of Fort McMurray.

However, Blake said residents must shelter in place and be ready to evacuate again if necessary. About 200 residents of the Centennial Trailer Park remain on mandatory evacuation and another 500 people in the Gregoire area were told to be ready to leave.

Blake and the fire chief pleaded with people to take personal responsibility to prevent fires because conditions are extreme.

"People, I'm asking for your appreciation of the danger and hazards that exist and to respect any sensible means, so please don't light your backyard fires this week, you can see how dry the conditions are," she said to reporters.

She also urged people not use ATVs or off-highway vehicles on the backyard trails and to stop flicking cigarette butts out of vehicle windows.

Darby Allen, regional fire chief for the Wood Buffalo municipality, said people must stay away from the fires, not only for their own safety, but because firefighters can't do their jobs if people get in the way.

"Today, we had a report from one of the water bombers that was flying over that there was a Jeep right alongside where the fire was burning. Someone's driven in on the trail, which is, by the way, completely crazy.

"It impacts our ability to continue. We can't carry on dumping water when we know people are down there because that's dangerous from that height."

Bernie Schmitte, forestry manager in Fort McMurray, said the wildfire was just 1.5 kilometres from the nearest residence and was 1.2 square kilometres in size.

Allen said no structures have been lost and there have been no injuries.

The fire broke out over the weekend and spread quickly due to tinder-dry conditions and high temperatures, which are forecast to continue Tuesday.

A fleet of air-tankers and helicopters dropped fire retardant and water on the flames as crews fought the fire on the ground.

The province said it will send more firefighters to the area and a heavy helicopter capable of dumping large volumes of water was en route.

"They have called in extra resources and we are absolutely grateful for the firefighters coming from other places to due battle for us here," Blake said.

Crews kept the fire just over a kilometre away from Highway 63, the major road link south to Edmonton.

Another blaze on the northern edge of the city called the Diamond Stone Ridge fire was being held.

There were no reports of injuries, but air quality was a concern because of the smoke.

Other areas reporting extreme wildfire hazards include the Slave Lake and Whitecourt regions northwest of Edmonton.

A wildfire that popped up Monday afternoon along a runway at the Whitecourt airport was quickly controlled, while a large place 45 kilometres north of Red Earth Creek continued to burn out of control.

With temperatures early in the week reaching up to nearly 30 C, provincial officials were issuing all sorts of warnings, including one for forested areas west of Calgary.

Restrictions and fire bans were in place for much of the province.

In May 2011 a sudden and quick-moving wildfire swept through the town of Slave Lake, destroying about one-third of homes and buildings and forcing thousands of people to flee the community.

News from © The Canadian Press, 2016